[A Case of MALT Lymphoma of the Rectum Treated with Intersphincteric Resection (ISR)].

A 60-year-old woman visited a local hospital complaining of melena. On colonoscopy, she was found to have 2 tumors in the lower rectum, each of approximately 10 mm in diameter. A biopsy of the tumors indicated MALT lymphoma, and the patient was referred to our hospital. We performed intersphincteric resection (ISR) with lymph node dissection according to the guidelines for the treatment of rectal cancer for 2 reasons. One reason was that eradication therapy for Helicobacter pylori was not effective in this case, and we needed to obtain an accurate histopathological diagnosis as to whether the patient had diffuse large B cell lymphoma (DLBCL). The other reason was that it was localized disease in the rectum, and that curative resection could be performed. MALT lymphoma of the rectum occurs frequently in the lower rectum and has a relatively good prognosis. It is important to consider the quality of life when selecting an operative method. ISR is thought to be a good option.